1. Field of the Invention
The present invention relates generally to wiper systems and, more particularly, to a wiper system that utilizes a resilient interface assembly for a worm-driven reduction gear motor for control of wiper assemblies.
2. Description of the Related Art
Wiper systems commonly employed in the related art include pivotally mounted wiper assemblies that are oscillated across a surface such as a windshield between an in-wipe position, typically located near the cowl of a vehicle, and an out-wipe position, usually associated with an A-pillar on the vehicle, in the case of the driver side wiper assembly in this representative example. It is typically desirable to maximize the angular velocity of the wiper assemblies between the in-wipe and out-wipe positions where the wiper assembly is moving across the windshield in front of the driver to reduce the duration of each wipe cycle. On the other hand, it is also desirable to limit noise and inertia loading by reducing the velocity of the wiper assemblies as they approach the wipe limits. These are two competing objectives that must be balanced in order to be successfully and economically obtained.
One long-standing design approach that has been employed in the related art includes the use of a worm-driven reduction gear motor, driven in one rotational direction, driving two separate wiper arms across the windshield of the vehicle. This approach requires a linkage system to convert the singular angular motion of the motor into the two-way linear reciprocal motion to drive both wiper arms. Typically, a “pal-nut” or metal wave spring has been used for regulating axial travel on an output shaft of the worm-driven reduction gear motor.
One disadvantage of conventional construction of worm-driven reduction gear motors is the loading deflection and axial and cross-axial movement of the output shaft. Another disadvantage is that the pal-nut and metal wave spring are used for regulating only axial travel of the output shaft. Yet another disadvantage is that the pal-nut and metal wave spring have single purpose/axis regulation of the output shaft. Still another disadvantage is that the pal-nut and metal wave spring have a linear spring rate and are subject to rust and corrosion. Thus, there is a need in the art for a wiper system including a worm-driven reduction gear motor to have an interface to damp mechanical inputs resulting from a connected load.